Although not exclusively, the present invention applies more particularly to a throttle lever for controlling a turbopropeller, that is to say an engine comprising a gas turbine driving one or more propellers by means of a reduction gear.
It is known that a throttle lever usually comprises:                a control lever which is capable of being pivoted either side of a predetermined position respectively forward and backward, under the manual action of a pilot of the aircraft, and which comprises a guidance means integral with said control lever and capable of interacting with at least a first and a second guide tracks which limit the movements of said guidance means and thus of said control lever;        said first guide track which allows the control lever to be moved continuously backward from said predetermined position, to control continuously the speed in reverse thrust; and        said second guide track, for the forward movement of the control lever, which comprises a plurality of detents capable of receiving said guidance means in order to allow the control lever to take one of a plurality of different positions, each of said positions controlling a particular forward speed of said engine.        
The presence of said detents allows a controlled management of certain particular engine speeds, such as the take off/go-around speed for example.
Such a throttle lever is not however well suited to certain types of flight or phases of flight, particularly military phases of flight such as in-flight refueling for example, for which the control of speed requires a very great sensitivity. The forward speed of the engine or engines must specifically, in such situations, be able to be modified in a very flexible manner, without interruption, and be adapted progressively. Such a sensitivity cannot be obtained with the aforementioned type of throttle lever, due to the presence of said detents which prevent an uninterrupted movement of the control lever.
Furthermore, due to this disadvantage, there is a tendency to limit the number of detents as much as possible, and therefore the number of particular speeds that can be thus managed individually.